Opening URL from Run window is giving "problem sending command to

When I click on Start > Run and type "http://www.google.com", it opens IE and gives an error dialog "There was a problem sending the command to the program"

whereas

When I click on Start > Run and type "iexplore -extoff http://www.google.com", it opens Google fine

Now, from the above behavior, it seems that the issue is related to any add-on, however, I have disabled all the add-ons in Internet Explorer.

Can someone please guide. how to troubleshoot this issue?

OS: Windows 7(32 Bit)

Browser: IE8

This might sound off topic.  But, I notice you are running IE8, WHY!??  I would certainly suggest upgrading your browser to the newer versions.  During this process it is likely to fix your initial problem anyways….

Otherwise, try to reassociate Internet Explorer with the HTTP protocol.  Do this in your default programs settings in control panel.  

Control Panel -> Default Programs -> Click Set your default programs -> Choose "Internet Explorer" -> Click Set this program as default.